At present, the passive optical network (PON), as a broadband optical access technology, usually uses a point to multi-point (P2MP) topology. The PON includes an optical line terminal (OLT), an optical distribution network (ODN), and one or more optical network units (ONUs). The OLT is located in a central office and connected to a service network through a service network interface, and implements access of multiple services according to a certain format. The ONU is located at a customer premise, and mainly implements service multiplexing/demultiplexing and user network interface functions. The ODN provides shared optical transmission media for a physical connection between the OLT and the ONU, uses a passive optical splitter to form a tree topology, and implement transparent transmission of a service.